with-test deps not installed after second call to opam install

[jchavarri]

In a local clone of an opam package, I ran a first install in a local package with just opam install ..

After this, I realized I had not installed the test dependencies, so I ran the following:

$ opam install . --with-test
[NOTE] Ignoring uncommitted changes in /home/javier/code/tyxml (`--working-dir' not active).
[tyxml.dev] no changes from git+file:///home/javier/code/tyxml#master
[NOTE] Package tyxml is already installed (current version is dev).

I was surprised that the test dependencies were not installed. @Khady pointed out that I could use opam reinstall . --with-test, and that installed the test dependencies successfully.

I guess the current behavior of install is expected, but as a user I assumed that calling install a second time with a different flag, would install any packages that are missing.

[kit-ty-kate]

I think this is a duplicate of #5567.
This should be fixed by #6209 very soon